The present invention relates to an articulating joint for coupling members, such as tubular sections, of various assemblies where the members are capable of transmitting axial, torsional and bending stresses in their extended position, yet are foldable for collapsing into a more compact arrangement.
More particularly, the joint of the present invention is virtually completely contained inside a tubular section to which it is coupled when in the unfolded or concealed position, and facilitates a simple, flush appearance of two connected tubular sections.
One contemplated use of the joint of the present invention is in a folding ladder consisting of two or more sections which are pivotally interconnected. The sections are arranged to permit the ladder to fold or collapse to a reduced size on the order of one of its ladder section components for portability and/or storage.
The articulating joint of the present invention provides means for movement, as well as coupling, of tubular sections without the use of another element such as a sleeve or external linking part. Joints which require sleeves are disclosed in U.S. Pat. No. 3,235,038 to Nesslinger and U.S. Pat. No. 2,895,757 to Kaspar. Furthermore, the arrangement of the present invention allows tubular sections to be folded without having to axially rotate them or unscrew an internally contained bolt or sliding shaft (see, for example, the joint disclosed in U.S. Pat. No. 3,655,297 to Bolen, Jr., which does not permit the sections to be secured in a folded position and only facilitates, with the aid of an additional part (sleeve 24), the fixing of the two sections when the sections are disposed axially opposite one another).